Electric gong



(No Model.)

J. P. TIRRELL. ELECTRIC GONG;

No. 328,982. Patented Oct. 27, 1885.

N, PETERS. Phnlulilhagrlpku Wiilllnglon, n. c,

' UNITED STATES PATENT OEETEE.

JACOB P. TIRRELL, OF BOSTON, ASSIGN OR, BY DIRECT AND MESNE ASSIGN- MENTS, TO JAMES F. EMERSON, OF WAKEFIELD, GEORGE O. CARPENTER, OF BOSTON, AND JOHN W. CARTER, OF NEWTON, MASSACHUSETTS.

ELECTRIC cone.

SPECIFICATION forming part of Letters Patent No. 328,982, dated October 27, 1885.

Application filed December 18, 1884. Serial No. 150,644. (No model.)

To all whom it may concern.-

Be it known that I, JACOB P. TIRRELL, of Boston, in the county of Suffolk and State of Massachusetts, have invented certai n Improvementsin Electric Gongs, of which the following is a specification.

This invention has for its object to provide an improved striking mechanism foran electric gong, whereby at a single closure of an electric circuit any desired number of blows can be given to indicate thetime for departure of railroad-trains and for other purposes.

The invent-ion consists in a gong-striking mechanism normally held by a detent which 1 is moved by the closure of a circuit through an elcctro-magnet to release the mechanism,

. and provided with mechanical devices which prevent the return of the detent to its holding position until the desired number of blows have been given, as I will now proceed to describe.

Of the accompanying drawings, forming a part of this specification, Figure 1 represents a side elevation of a gong-striking mechanism embodying my invention. Fig. 2 represents an enlarged elevation of a portion of the mechanism.

The same letters of reference indicate the same parts in all the figures.

In the drawings, a represents a gong, and b the hammer thereof, pivoted at c to a fixed support.

(1 represents a wheel having ratchet-teeth cut in its periphery.

6 represents a spring secured at its outer end to a fixed support, and at its inner end to the arbor of the wheel (1, the spring acting to rotate the wheel in the direction indicated by the arrow in Fig. 1 when the mechanism is re- 0 leased. A dog, f, pivoted to the end of the hammer-arm, is held by the weight of the hammer in contact with said wheel.

9 represents a lever pivoted at h to a fixed support, and connected by a rod, 7:, to ashort 5 arm, j, on the hammer-arm, said rod having a slot, is, through which the pin passes that connects the arm 1' to the lever 9, said slot permitting the lever to oscillate, as indicated by dotted lines.

at represents an electromagnet, and a an armature therefor. Said armature is pivoted near one end at 0, and its swinging end drops away from the magnet by gravitation and engages with the swinging end of the lever g, as shown in full lines in Fig. 1,when the electro magnet is not energized. The armature, when engaged with the lever g, constitutes a detent which prevents the striking mechanism from operating, the lever 9 being thus held so that a block, p, pivoted to it at q, supports a stud, r, on the hammer-arm and prevents said arm from swinging on its pivot, the hammer-arm bearing against one end of a spring, 8, which is pivoted at t, and presses the other end of said spring upwardly against a pawl, a, which engages with one of the teeth of the wheel d, and holds said wheel against the force of the spring 6. a

When the electro-magnet is energized by the closure of the electric circuit through it, the armature or detent n is attracted, as indicated in Fig. 2, and by dotted lines in Fig. 1, thus releasing the lever g and allowing the weight of the hammer, acting through the stud r on the inclined edge of the block 0, to force the lever 9 forward, as shown in dotted lines in Fig. 1, the hammer being thus released and allowed to drop. This movement of the hammer forces the dog f upwardly against a tooth of the wheel (1, giving the wheel a very slight backward movement, which issufficient to release the holding-dog a, the spring s being deprived by the same movement of the hammer of its upward pressure on the dog a; hence the dog drops, as indicated by dotted lines, and thus leaves the wheel free to rotate. The spring 6 now rotates the wheeld, atooth thereof bearing against the hammer-dog f, and through said dog swinging the hammer upwardly, causing it to strike the gong.

When the hammer swings upwardly, the lever g is caused by a spring, a, to resume the position shown in full lines, and is again engaged by the armature or detent n, the latter having been released by the breaking of the circuit through the magnet. A single closure of the circuit therefore causes thehammer to give a single blow.

The mechanism above described is not of itself a part of my invention, but constitutes mature after the first blow, caused by the atthe striking mechanism of what is known as the Crane gong."

In carrying out my invention I provide mechanical devices whereby when the wheel d is 5 released, as above described, the armature or the detent n is held away from the lever 9 until the desired number of blows have been given by the hammer. To this end I'provide the wheel d with a series of pins or projections, 1), which may be arranged in any desired order, each pin acting in turn on a lever, c,which is pivoted at d, and bears at one end on the under side of the armature or detent it. When a pin 1) is brought by the rotation of the wheel in contact with the lever c, it turns said lever on its pivot, causing it to hold up the armature or detent, as shown in Fig. 2, so that it will not arrest the lever g, the wheel d continuing to rotate and throw up the hammer while the detent is thus held. Holes 0 are provided in the wheel 01, one for each tooth thereof, the pins or projections bbeing placed in said holes in accordance with the number of blows to be given at each operation. Thus armature would be continually held up and the hammerwould be operated until the spring 6 loses its force.

In the arrangement shown in the drawings every alternate hole has a pin 1), the result of this arrangement being to hold up the artraction of the armature, until another blow has been given, the armature being then re leased and arresting the mechanism after two blows have been given. If the pins be arranged with intervals of two holes between each pin and the next, one release will give one blow only and the next release two blows. By arranging two pins in'successive holes with intervening spaces of two holes one release will give one blow and the next release three blows.

Instead of pins inserted in orifices, lugs or if one pin were provided for each tooth the ears may be attached tothe side of the wheel 5 intervals, while my above-described mechanism enables such single closure to cause any desired number of blows.

I claim-- 1. In an electric gong, the combination of striking mechanism, substantially as described, a detent which automatically engages with and holds said mechanism and is withdrawn therefrom by the closure of an electric circuit, and mechanical devices, sub stantially as described, whereby the detent is heldv in an inoperative position until a predetermined number of blows have been given, as set forth.

2. In an electric. gong, the combination of the striking mechanism having a spring-impelled toothed wheel, a detent which automatically engages with and holds said mechanism, and is withdrawn therefrom by the closure of an electric circuit, pins or projections secured to said wheel, and a pivoted lever bearing against the detent and projecting into the path in which said pins move, as set forth.

In testimony whereoflhave signed my name to thisspecification, in the presence of two subscribing witnesses, this 1st day of December, 1884,

JACOB P. TIRRELL.

Witnesses: Y O. F. BROWN, R. J. POWERS. 

